(a) Field of the Invention
The present invention relates to a thin film transistor array panel and a manufacturing method thereof.
(b) Description of the Related Art
Liquid crystal displays (LCDs) are one of the most widely used flat panel displays. An LCD includes two panels provided with electrodes, a liquid crystal (LC) layer interposed therebetween, and a pair of polarizers attached to outer surfaces of the panels. The LCD displays images by applying voltages to the electrodes to generate an electric field in the LC layer, thereby rearranging LC molecules in the LC layer to adjust transmittance of incident light.
Among LCDs, including field-generating electrodes on respective panels, a kind of LCDs including two panels provided with respective electrodes and thin film transistors (TFTs) for switching the voltages applied to the electrodes are most commonly used. The TFTs are provided one of the two panels.
A gate wire or a data wire transmitting signals are typically made of low resistant material such as Al and Al alloy for preventing signal delay. The data wire has a multi-layered structure including refractory metal such as Cr since it contacts silicon layer.
When manufacturing the LCD, the panel including the TFTs is usually manufactured by photo-etching process with masks and it is desirable to reduce the number of the masks for decreasing product cost. For this purpose, it is suggested a technique of patterning two layers by photo-etching with a single mask to have different patterns, thereby completing the TFT array panels.
However, when patterning conductive multi-layers for forming signal wires in the above-described manufacturing method of the TFT array panel, there is a problem that it is difficult to etch one of the conductive multi-layers and thus to patterning a signal wire.